The edits on this comment make it the second best HN comment of all time.
The whole thread is pretty hilarious. In another part of the same thread there is this comment:
we're in a similar space -- http://www.getdropbox.com (and part of the yc summer 07 program) basically, sync and backup done right (but for windows and os x). i had the same frustrations as you with existing solutions.
let me know if it's something you're interested in, or if you want to chat about it sometime.
drew (at getdropbox.com)